The purpose of this project is to develop new chemotherapeutic approaches to cancer by studying new agents and biological systems for evaluation of potential antineoplastic agents. The topics of current interest are: 1) antitumor activity of actinomycin and anthracycline antibiotics; 2) biochemical pharmacology of potential antineoplastic agents including PALA, maytansine and inhibitors of protein biosynthesis; 3) resistance to anthracycline antibiotics and Vinca alkaloids; and 4) chemotherapy of human colon carcinoma xenografts.